Johnson in the U.S. Pat. No. 4,240,377 discloses a method and apparatus for carrying out fluidized bed combustion and transferring heat produced thereby to a boiler which includes providing a fluidized bed of particulate matter and introducing fuel particles thereinto, causing a portion of the fluidized bed constitutents to flow upwardly through a heat exchanger which is essentially free of any obstructions to the flow, and reintroducing the portion of fluidized bed constitutents which flow through the heat exchanger, back into the fluidized bed.
Center Line discloses a feed valve positioner and flow valve which may be adapted for use as applicant's particulate solids feed valve positioner and solids flow valve referred to later in the specification as 1 and 2 respectively.
Foxboro Company of Foxboro, Mass. 17-143 April 1963, p. 1 discloses controllers with set point transmitter which may be used in applicant's invention as differential pressure controller 8 as discussed later in the specification.
Foxboro Company of Foxboro, Mass. at 5-616, September 1955, p. 1 discloses d/p cell transmitters which may be used in applicant's invention as differential pressure transmitter 4.